/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.shardingsphere.governance.repository.zookeeper;

import lombok.AccessLevel;
import lombok.NoArgsConstructor;
import org.apache.curator.test.TestingServer;
import org.apache.zookeeper.KeeperException;

import java.io.File;
import java.io.IOException;

@NoArgsConstructor(access = AccessLevel.PRIVATE)
public final class EmbedTestingServer {
    
    private static final int PORT = 3181;
    
    private static volatile TestingServer testingServer;
    
    /**
     * Start embed zookeeper server.
     */
    public static void start() {
        if (null != testingServer) {
            return;
        }
        try {
            testingServer = new TestingServer(PORT, new File(String.format("target/test_zk_data/%s/", System.nanoTime())));
            // CHECKSTYLE:OFF
        } catch (final Exception ex) {
            // CHECKSTYLE:ON
            if (!isIgnoredException(ex)) {
                throw new RuntimeException(ex);
            }
        } finally {
            Runtime.getRuntime().addShutdownHook(new Thread(() -> {
                try {
                    testingServer.close();
                } catch (final IOException ignored) {
                }
            }));
        }
    }

    /**
     * Get testingServer connection string.
     *
     * @return connection string
     */
    public static String getTestingServerConnectionString() {
        return testingServer.getConnectString();
    }
    
    private static boolean isIgnoredException(final Throwable cause) {
        return cause instanceof KeeperException.ConnectionLossException || cause instanceof KeeperException.NoNodeException || cause instanceof KeeperException.NodeExistsException;
    }
}
